Best available cop



Dec. 18, 1928.

R. C. LEAKE TRAIN CONTROL RELAY Filed Nov. 5, 1921 a Sheets-Sheet 1 Dec. 1 8, l 928.

3 Sheets-Sheet Filed Nov. 3, 1921 8 mm on mm i 3 mm 2 2 i 2 W S 8 MN E 8 NH Z :H 3 6 3 9 C H a t r w nu mu 5 m n 2 V g i mm 3 8 6m Patented Dec. 18, 1928.

UNITED STATES ?ATENT OFFICE.

RICHARD C. LEAKE, OF ROCHESTER. NEW YORK, ASSIGNOB TO GENERAL RAIL KAY SIGNAL COMPANY, OF GATES, YORK, A CORPORATION OI NEW YORK.

TRAIN-CONTROL RELAY.

Application filed November 3, 1921. Serial No. 512,559.

This invention relates to electrically operated relays, and more particularly to relays for'use in automatic train control systems for. railroads, and adapted to be carriedon a locomotive or other railway vehicle.-;;-.-,-n: -;l. v 'Ihexc'ar relays used-in cab signal-: or train" control systems; for railroads, being carried. on; :a l IOCOIIlOtiVexOI similar vehicle, are esubjectedfi to irregular. and peculiar shocks, jars iand a vibrations ofmagnitude and intensity not foundin any otherservice. Imrcertainztypes of train control systems, ially incthe intermittent inductive type in livhich the=controllingzimpulses or influencesare communicated-Efrem the trackway llOf-tli imovin wehicle' through an interveningminzg'ap. y= si1itabl'e trackelements locatedr at interval's;along; the track, it is desirable to emplo'y a-:car relay-capable of working reliably on small'cur'rentchanges of'--i-el'atively short-duration, a relayof the tractive armature. type :beingconsidered veryr'fiidient and: desirable for such systems. --::';Z.' -:..-=.v T a order-tor Tobtain; is oh sensitive} and quiek acting-relay, it: isnconsidered preferable to empldvli lit-moving; parts having little inertiaaran woperable: on small amount ofEenergyZ;-but it is ifound'that when a relay is:thusx constructed ism-as :to? operate properly and%.-efiicie1itly under these conditions', the severe jar" andcvibration -t'o which the zpelaygist'subjecfd tendstol caused false operatioirc A single .fa'lse operationis, of course, 'rohibiti-ve .'in a train control systm,'vvh1ch m'ust-by its verymature'be dependabl'e; in .its performance; and since the carequipment is-ordinarily organized, by the use of a stick feat-urein connection with th'ereIay-or. device controlled thereby,-a single momentary opening of the-relay contacts willresult in aibrake'applicat-ion, or the imposition of some other form of automatic control; sot-hat only one momentary operation of the relay'contacts 'by-jar and vibration produces a false'control that'rendeis't-he 'whole system seriously defective. A relayof the tract-ive armature type is preferably employed in a normally closed circuit system, which is considered good practice in railway signaling and control systems; for the reason that a failuroof the circuit will be onthe side of safety, in that, such failure will operate the mecl1anism controlled bysuch relaythe same-:way as a danger condition, thereby =making -a brake application or in1pcse -some' ;-other form of automatic control.-; In circuits of this kind, as wellasimman .othersfitis expedient to employ airelay 'aving an; op,- crating characteristic by -Vi ll;\1e -::.Whi(h the drop away.- current," that ;is, the, current that will just 'drop the,- armature,-,is very high as compared with thegfipickup current, that is, the current. ,which pick up the armature. ;;lVith -;tliese; a'nd other-{considerations in rmnd, the primary.- purpose,- of the present at: invention is to c'onstructm,simple zeflieient, and reliable relay ,which vv-ill-be. relatively quick acting and'sens'itiveyandmt the same time will not be iriiproperly or gfalsely pp,- erated by the-iIf1eg\ll1l $l1OCk:flJICl-Mbta} tions encountered Ton! locomotives: Genenally stated, it is proposed; in this,invention to makethe movingpartsz of the relayas light as consistent with; .efiicient andgreliable performance; to-, balance the armature ,and other moving parts='- substantially against so rectilinear and curvilinear -,vibration ,that

is, provide each reciprocating part withean oppositely movin reciprocating,- part;,cou,- pled thereto, '5 hereby-z; balancing.- them against each other; iandprovidel-eacli 11102- .tati g element? with ,a .oq nte balancing arc.- tatiible element. coupled-thereto to rotate in the opposite direction,: thereby -balancing these rotatable elements, against eachgother; to provide compensatingmeans in'rthe strucno ture of the relay jwherebyithegattractive force of: the-armature will-bel practically balanced 7 against; '.-.the action} of ,9,, spring throughout the entire 'moveinent of thc armature,-by virtue of which the .fdropaway current will be.almost-equal-;to the {pickup current;.to, forni an-eflicient magnetic circuityand Iingeneral adapt and-organize the parts o'fsatractivegtype-relay ioiyetficient and reliable operation under.,.severe shocks, jars and vibrations.

Other-features and advantages bfltlltljfl" vent-ion will appear hereinafter" asthe description progresses.

In describing the invention in detail, 11-1 ercnce will be made to the acconnmn sia; drawings, in which Fig. is a plapyiew of the device cmbodymg this invention;

Fig. 2 is a side view of the device partly shown in section for clcarncss;

Fig. 3,- is :i' top yie y of one end of the devicc'nfitli the top plate removech certain parts being cut away for clear-rages;

Fig. 4 1s a section taken on line -.1 "I Fig. 1, viewed in the direction of tha- :u rows; and

'Fi 5 is an end View of the (lrcirc showing the left hand end of' the device as shown in Fi l.

The particular constrgction illustrated, embodying the present invention comprises afmmeconsistifig of two angle. bars l faslyned'togcther by a crossbar 2 at. one end which is f astened thereto but spaced therefrom by two bolts 3 with spring washers ant. spacing members 45 and at the other end th ba'rs ai'e'held together by a plate 5 riveted thereto byrivcts forming upstanding posts Son which is supporteda top plate 7-. Two spacing sleeves 8 are provided between the two plates through which screws pas'sinto le s 9'forming a support for one endfof the rgme. jAcore' 10' made up of lamiii'a ted mfg iron of: H- shape is SIllJPfilt-Bt'l on'tlie'crossbar-2 and plate 5 by any suitable 'means a. bolt hayinga'cylindrical not forming sf-third leg ll'a'nd; rivets '12 being: shown in"tliis'insta nce (see Figs. 4 and I). The middll: bar of-=t-h e Hshaped-core is provided with 'a"coil '13,-which is'h'eld imposition by a fqnr prong spring'plate 14 Pins 15 pass throu h the crossbav and corc having their opposite ends provided with spools l6, a portion of eilch' spool being cut away to proyide knife 'ezgge bearingsg 7 These spools am-hr-ldin pla'ce"by cotter pins passing through-'each 'en' (l"=of 'thepins. "lfwo opposite dispqsedarmatnres'l'i haying one end bifurcated; and each bifurcation bent in the shape of a w rest againstthe knife edges. Tvyo parrs'of steel spring; 18 (see Figs 1 and --5)"'arepositioned diagonally het aiecn the W-sl iapedportion ofdhe 'arniat nrcs forming'crosse's. Byjloolying at Fig. 1 of the drawing it'wi lhli'e noted that by moving the ermatures in opposite directions, the compression oi the springs will not be changed materially] By makingthe spring sufficiently h eav the movement of one armature will move he other in-"the opposite direction. These springs are provided to hold the armatnres against theirlknifc edge bearings permitting movementof the arinatares iii-"oppositedirections siznultanconsly and have very little, if any, tendency to bias the armatni'e's in one direction or the other. Th dp it nds otthe aiginaturcs have. a non-magnetic plate 19 riveted: thereto which p: event the amiaturos from making physical contact with the core. The object for proriding this plate is to improve the performange characteristic of, the relay, as pginted out hereinafter.

The free ends of the armature 17 are pivogally connected, torurrgd links 20.1 split P n 2 h he and qt he iqkfi ed to -a cross arm 22 carried by a die 22} and are fastened thereto by simi- 24-. The spindle 23 is pivoted in the bottom plate and extends through a hearing fastened to the top plate 7.' This construe-that obl ges the arniatures 1.7 to more oppositely simultaneously and therefore the 'arnmturcs themselves will be bah against each other for, both,' recti- The spindle 23 and the mechanism Carrie-(l there-by, is however only balance'dfin itself against rectilinear disturbances and ar st be counterbalanced as will up car here? inaftem The spindle 23 is biase in a, dir-cct-ionto hold thearmatni'es l'i an ayfrom the pole pieces of the core 10- byna' spiral spring 26, having its outside endw fnstenad in a casing 27, this casing ed to the bearing plate flbyscrews 28'. The top end of the spindleh23ieanries a. flanged socket 29 which is adpista blysecnred them: to uy a sct screw. A stiidfiq'hayiggarqll 0-1- 3l oi insulating material journale'd there? to by means of a. metalliq-sleeve 3a.,- is riveted to the flanged socktahfll), apdiidhmctrically opposite to thisi'rollen is.a counterweight 33 riyeted.=-'to. the flanged socket 29 to connterbalande therollei: 31.- aad the supportinp means therefor.

' The roller 31 cngagsibetweenthe of a U -shaped:memberl34 rivetedtoa switch supporting memben. 35, whiglx'is'. piviotiilly supported in a stationary. bracket 36. bracket 36 is bolted to. pec les tal:39-by a halt 37 and binding-post 38 but insulated ij-rom a. pedestal- 39, which is fastened on tliezplate 7 by suitable tastcninganeans bolts 40 being used in this instance; 'Dbels'witch support.- ing: member 35-is prdvid'e d with a. long: coill act spring 4-1 slightly tensions-d; to. Test against the curved -end' =0 th.e liiemhenxifii when the relay isdeenergized, a non -corr0 sii\-'e contact 45. J In osd'eeto con- 01 .1 and curvilinear vibration and disturb= DUUS duct currrent from the binding;post;-38.hto

the movable oontact spring.- a veryrflexh bie conducting wireorpigtail-491zhasbeep connected between the post and: contact spring A contact-post e3,- alsossving'. as'a binding-post. is fastened. to thetop pletefl' by bolts andinsulating-sleeves'andzwasheys in the usual manner.' This contatpostffi is drilled and tapped crosswise. andshas a conductingcap screw. provided: at itsend with a. non-corrosive contact; 45, screwed therein, so that the position oiisthe Contact may lv; \zlllCd hy taming-the. cap screw.

til)

Each of the armatures is provided with an adjustable stop to limit the distance the spring may move it away from-the pole pieces. These stops consist of a strip of metal 46 bent back on itself and bolted onto the bottom plate 5. The slot formed by so bending the strip is drilled and tapped and contains a stop screw 47 turned into the slot at suit-able distance, against the end of which its corresponding armature may abut. To lock the stop screw 47 in position, a hole is drilled in the strip of metal crosswise and adjacent the stop screw, into which a lock screw 48 is screwed to bind the strip and thereby hold the stop screw 47 in locked position.

Electro-magncts of the tractive iron armature type have a performance characteristic, which under certain-conditions is undesirable, especially when used in a relay which is to beused in' an energized circuit and 'is'to-open whenthe current has dropped slightly in value, unless" some modifying or compensating means is' provided. -In an electro-ma'gnet" of this kind 1 the tractive' force varies as the square -of the flux through"the'armature', and the-flux varies approximately. inversely as the square of the distance ofthe air gap during the movement of the armature, this 'relationfbeing true 'if the reluctancei'of' the' iron is negligibleias compared with reluctance at g the air gap;

and therefore is 'apl'no zimately"true where the air gap is appreciable? In' the particular relay embodying the present invention,"such modifying means has been provided by having the efiecti-ve lever armof its-mechanical transmitting system ivziry approximately in accordance with the "variation l of the trac tive force "of the armatures, "due to the change in the air gap.

In the 'particular' constructionl illustrated, the non-magnetic 'or residual stop plate 19 has been-rivetedtothejarmaturcs so' -that the air-"gap can--'not-b ecorne zero. This'is desirablefor if the armaturesicduld-physi-j cally contact the core of the relay, the residual magnetism would tend to'hold-the armatures in contact with the-core, anda very'large redu'ctioni-in current would be necessary to drop the 'armature's a way from the core; "A 'further 're sonpror providing the' non ma'gne'tic' residual stop plates 19 is to use "a 'niovement of the; armatures be tween their extreme po'sitions wh'ere the rate of change of tractiveforce of thearmatur'es is low, since'it would difficult to provide a practical mechanical mechanism to compensate for such'variation of force for small air gaps, the variation of this forceitheoretically approaching infinity as the air gapapproaches zero. Desiring, however, to have the tractive force of the armature approximately counterbalanced by the fort-e of the spring at ditle'rent pointsof movement of the armatures 17, a special-scheme of connecting the armature to the spring is made use of in this invention in the following manner;

The curved links 20 are connected to the crossbar 22 to change the practically constant force of the spring 26 into a force at the point of pivotal connection of the curved links 20 to the armatures 17, which rapidly increases as the armatures approach the core 10.- By looking at Fig. 3 and referring to the angle between the line of action of the free ends of the armatures and the crossbar as the angle A,'it will be observed that the ellcctive lever arm of the compensating mechanism upon which the spring acts varies as the sine of the angle A. In order to compensate for-variation of tractivc force of the armatures for very small-air gaps, such as -'would 'be' encounteredifs no nonmagnetic-stop plate=were used, it would be necessary to make' theangle A-- very small, thus bringingthe crank comprisingthe crossbar and the curvedlink pivoted thereto almost on'=center. This is undesirableon accountof the instability of the device that would result,- because'any: small' amount of variation dueut'o worn pivotal connections, and the 'like,=vrould change the operating characteristicappreciably, t

Although itfis desirable to compensate for the rat'e of'change -of tractive force,- of the armatures,- andin i this way increase the dropaway -current as compared with the pickup current, it'is -not=necessarily desirable toentirely compensate for'this rate ofchange; because='-by 1 so doing, no force would -'be 1 left 'to provide contact pressure. For ordinliry' working conditions, therefore, it is, preferred tocompen'sation for the rate of change of'tractive force=to an extent to just leave suflicient force to make the necessary contact pressures To? determine in practice 'the' relation 'of "the angle-1A to the aii ga'p'to obtain this compensation rit is expedient to plot a curve, withthe ai 1-. gap as 'abscissas andthe sum ot the forces of the twoar-mat-ures as ordinates This may easily be done byremoving-the spring 26 and measuring the'force at the pointiof pivotal' c'onnectionj of the 'curved links-2O to one of the arr'naturesjl'. The spl in may then be put'back 'in' place and tensioned approxi mately to the"desire'd"amount, and the force on one of the armatures '17 due to-theispi ing 26' through the'c'urved' -links' may then be nieasuredatthe same point for different-air gaps with the relay deenergized, and by plotting this curve on the same sheetthe relation' of the tractiv'e force of the armature, to force-ofthespri ng transformed by the compensating mechanism may be observed. 1 By varying the-angle -A- with respect to the air gap and byvarying-the ten sion of the spring, a relation-n'iaybe found lilo prising a biased movable contact, and two armatures counterbalancing each other operatively connected to the contact by counter-balanced parts including members mounted to turn about central axes.

9. A relay for use in connection with vehicle carried apparatus of train control systems comprising, two movably mounted armatures, pivotally mounted and rotatably. counter-balanced means mechanically connected to both of said armatures and a spring on said pivotally mounted means for biasing said mechanism to a predetermined position.-

10. A relay comprising, a pair of biased armatures balanced against each other, a pivotally mounted contact spring, and means including a pivotally mounted lever of variable effective length for varying the effective force transmitted by said arma-t-ures to said contact.

11. Means for operating a pivotally mounted contact spring by a spindle comprising, a pivoted driving lever arm and a pivoted driven lever arm, one of which has a variable effective length, the variable effective length automatically changing to compensate for the variable pressure of said contact spring. 7

12. A relay comprising, a core, an armature associated with said core, contact means biased in normal position, and mechanism including a pivotally mounted and axially balanced element counter-balanced for all positions thereof connecting the armature with said means and varying the force transmitted from the armature to said means to produce a substantially uniform torque by said means.

13. A relay comprising, a core, knife edge bearings adjacent to one end of the core, armatures having indentations resting against said bearings and members for holding said armatures against said bearings, and for operatively connecting said armatures to move oppositely to balance the same against each other.

14:. A relay comprising oppositely positioned knife edge bearings, armatures resting against said bearings, and resilient means operatively connecting said miniatures and holding them against said bearings.

15. A relay having two armatures pivotally supported on opposing knife edge bearings, and two members connecting said armatures and transmitting thrust-s from one armature to the other tending to turn them in opposite directions.

16. A relay having two armaturcs pivotally supported on opposing knife edge bearings, members having knife edges engaging said armatures to move them in opposite directions.

17. A relay for use on railway vehicles comprising, a rotary element, electro-responsive means for operating said element, a pivotally supported contact element having a contact spring, an adjustable stationary contact adapted to cooperate with said contact spring, and means for operatively connecting said rotary element to said contact element in a manner to afford a variable turning ratio between said elements, said last mentioned means being constructed to compensate for variations in the tension of said spring due to engagement of its contact with said stationary contact.

18. A relay of the tractive armature type comprising, a core, a winding on said core, an armature, a stationary contact, a movable spring contact, and means for operating said spring Contact by said armature so that substantially a constant surplus operating force exists for moving said contact spring for the various positions during which the stationary and movable contact cooperate including, means for compensating for variations in the tractive force between said armature and core, and compensating means to take care of the additional pressure to be overcome as the tension of the contact spring changes.

19. A relay of the tractive armature type comprising, a core, a Winding on said core, an armature limited in its movement to and from said core, a stationary contact, a movable spring contact, and means for operating said spring contact by said armature so that substantially a constant surplus operating force exists for the various positions during which the stationary and movable contact cooperate including, means for compensating'for variations in the tractive force between said armature and core, and compensating means to take care of the additional pressure to be overcome as the tension of the contact spring changes.

In testimony whereof I hereto atiix my signature.

RICHARD C. LEAKE. 

